Orca Series linear bearing lm8uu x-carriage - Selectable Timing Belt

I have not finished designing my own X carriage yet but need to get my Orca finished for now. http://www.thingiverse.com/thing:19837 However if you prefer this version I will leave it here. Raggies X carriage looked about the best of the ones on thingyverse, the only problem is I wanted to use T2.5 timing belts and the original seems to be for T5 only. SO using the orgiional STL I have made an open SCAD script so that you can choose what sort of timing belt you want to use (so long as it is T2.5, T5, T10 or MXL, for now at least) by using my timing belt library found here http://www.thingiverse.com/thing:19758